Joint Optimization Decision of Online Retailers’ Pricing and Live-Streaming Effort in the Postepidemic Era

The isolation requirements of the coronavirus epidemic and the intuitive display advantages of live-streaming have led to an increasing number of retailers shifting to social live-streaming platforms and e-commerce live-streaming platforms to promote and sell their products in real time. However, the provision of live-streaming services will also incur high live-streaming effort costs. In this paper, we develop two decision models for retailers to sell goods through a single online shop and both online shop and live-streaming room; we also present the optimal decisions of pricing and live-streaming efforts. Furthermore, we identify the profitability conditions for retailers to determine when to provide live-streaming services. In addition, we examine the impact of the provision of live-streaming services on the optimal price and live-streaming effort. We obtain three findings. First, there is a unique optimal decision on the price and live-streaming effort under certain conditions. Second, when the effect coefficient of the live-streaming room reaches a certain threshold, there are enough customers who enter the live-streaming room to watch and buy and it is profitable for retailers to provide live-streaming service. Finally, the optimal price and live-streaming effort increase with the increase in average return loss, the effect coefficient of live-streaming effort, and the extra return rate and decrease with the increase in the proportion of customers who choose to buy in the online shop and the price discount coefficient in the live-streaming room.

Application of Wellbore Strengthening Techniques in Carbonate Formation Solves Lost Circulation Challenges During Liner Running and Cementing

For many years, the oil and gas industry has deployed techniques which enhance formation strength via the successful propping and plugging of induced fractures. Induced fracture sizes have been successfully treated using this method up to the 600 – 1,100-micron range. Static wellbore strengthening techniques are commonly deployed to cover 1,000 micron and all fracture size risks underneath. The deployment of wellbore strengthening techniques has historically been confined to permeable formations. In most cases, wellbore strengthening has been deployed to operationally challenging sand fracture gradients or, where boundaries are pushed, lower ranges of permeability, such as silts. The subject of wellbore strengthening in shales or carbonates to this day, remains a challenge for the industry, with very few documented success stories or evidence of sustained ability to enhance fracture gradient across a drilling campaign. This paper covers the history of lost circulation events which have been reported in the Khazzan/Ghazeer field in the carbonate Habshan formation. It also describes the design changes which were introduced to strengthen the rock and enable circulation/returns, during liner cementation. The design work built on experience applying wellbore strengthening techniques in carbonates in the Norwegian sector of the North Sea. This work is also summarized in this paper. The Habshan carbonate formation in Oman presents a lost circulation challenge through an ‘induced’ fracture risk. Since the beginning of the drilling campaign in the Khazzan/Ghazeer field, the Habshan formation has repeatedly experienced induced mud losses during well activities such as liner running, mud conditioning with liner on bottom and cementing, when the formation is exposed to higher pressures, less so during drilling. The Habshan challenge in Oman has led to regular, significant lost circulation events during cement placement, adding operational cost and more importantly, presenting difficulties around meeting zonal isolation objectives. Through previous field experience in Norway, a set of criteria was developed to qualify a standard pill approach to carbonate strengthening. The currently deployed strategy is designed to address both the risk of induced fracture by propping and plugging (wellbore strengthening) and provide some ability to seal natural fractures which are often encountered with carbonates, or similarly flawed rocks. The strategy deployed aims to cover these two risks with a blanket approach to lost circulation risk in carbonates. The success of this approach is demonstrated using well performance data from a total of 43 wells drilled before and after the introduction of the wellbore strengthening strategy. As it was initially assumed that wellbore strengthening could not be applied to carbonate formations, other techniques had been tried to prevent lost circulation. Those techniques provided mixed results. Since the implementation of wellbore strengthening significant improvements in achieving zonal isolation requirements and reducing fluid losses have been documented.

Novel Automated Light Foam Cementing Set-Up Brings Operational Efficiency to Major Operator in Norwegian North Sea Sector

As oil and gas operators are constantly looking for ways to increase efficiency in their operations, one area of well construction that is becoming increasingly popular is in the field of foam cementing. Foamed cement slurries are designed to have low density with relatively high compressive strength to enable operators accomplish their zonal isolation requirements. In addition, the enhanced slurry mobility of these energized fluids leads to a high displacement efficiency to ensure uniform cement coverage in the annulus. The use of foamed cement slurries particularly for top-hole sections in deep-water environments has increased over the past decade. For large volume jobs such as these, operators utilize the standard Automated Foam Cement System (AFCS) which comprises of high-pressure nitrogen pumps /converter and portable liquid nitrogen tanks. The AFCS automatically controls nitrogen and cement slurry based on the downhole rate and precisely maintains a desired foam cement density. For smaller volume jobs, the main constraint to deploying the standard AFCS is mainly rig deck space limitations, thus a "light foam package" was developed. The light package, fully developed in Norway, maintains the already well-established characteristics of automation from the standard AFCS; with the added benefit of minimizing footprint on board the rig with equipment which includes foam manifold, gas bottle rack and nitrogen control flow valve vs. the conventional liquid nitrogen tanks, pumps, and back up equipment. Other advantages of this set up include much faster rig up time due to smaller and lighter liftsimproved HSE benefits of eliminating liquid nitrogen handling; as well as limiting number of people required offshorefull job accuracy and automatic control with the utilization of mass flowmeters to measure nitrogen and cement rates with precisionrobust system with 100% redundancy of critical components This publication highlights the job details from a light foam job performed on a 30in conductor in a well on the Norwegian Continental Shelf, with the objective to cement the entire conductor length to seabed. This job was conducted in a field where numerous past cement jobs had failed to bring cement up to seabed and top up jobs with grout were the norm to achieve top of cement. With this simplified foam cementing process, the vision is that this kind of system set-up can make foam cementing a reality even in the most remote of locations and/or locations with small deck space, with reduced start-up costs.

Review on Vibration Isolation Method for Atomic Interference Gravimeter

The cold atomic interference absolute gravimeter is an ultra-precision instrument for measuring absolute gravity acceleration. At present, the highest measurement accuracy can reach the order of micro gamma. It has important application value and research significance in many disciplines, such as geophysics, resource exploration and assisted navigation. Because of its ultra-high precision, the ultra-low frequency micro-vibration noise on the ground has become one of the important factors affecting its accuracy, and it is also the bottleneck of the further development of gravimeter. Firstly, based on the theoretical and experimental results, this paper analyzes the vibration isolation requirements of atomic interference gravimeter. Secondly, it summarizes the research progress of atomic interference gravimeter isolation system and introduces three main isolation methods: passive vibration isolation, active vibration isolation and vibration compensation. Finally, the future development direction of atomic interference gravimeter isolation technology is analyzed and prospected.

EP.TH.305Savi Scout Radar versus Wire-Guided Localisation in Breast Cancer Surgery: A Systematic Review and Meta-Anaylsis of Surgical Outcomes

Aims Wire-guided localisation (WGL) has been the standard technique for localisation of non-palpable breast cancers (NPBC) for almost 40 years. However, WGL has disadvantages including peri-operative scheduling challenges and patient discomfort. Savi Scout localisation (SSL) is a novel alternative that utilises an implantable wireless non-radioactive reflector. A systematic review and meta-analysis was performed to compare outcomes of SSL versus WGL in NPBC surgery. Methods Embase, MEDLINE, PubMed and the Cochrane Library (1946 to December 2020) were searched using PRISMA guidelines for studies comparing SSL and WGL in NPBC surgery. Outcome measures analysed were operative duration, positive margins and re-excision. Results were pooled into meta-analyses using a Mantel-Haenszel Random-Effects model as Odds Ratios for dichotomous data and Mean Difference for continuous data. Results Four eligible peer-reviewed cohort studies involving 808 patients were identified comparing SSL (n = 462) and WGL (n = 346). There was no significant difference between SSL and WGL in operative duration (95% CI -0.27, -7.89 to 7.34, p = 0.94), positive margins (OR 0.73, 0.36 to 1.45, p = 0.36) and re-excision (OR 0.62, 0.33 to 1.16, p = 0.13). Inclusion of two non-peer-reviewed cohort studies (additional SSL n = 143, WGL n = 424) altered statistical significance for re-excision in favour of SSL (OR 0.55, 0.36 to 0.83, p = 0.004). Conclusions This study demonstrates that SSL is a safe and effective alternative to WGL. SSL uncouples pre-operative localisation from surgery, reducing scheduling challenges. This is particularly useful in the current COVID-19 climate, with pre-operative patient self-isolation requirements. SSL may decrease re-excision rates. Randomised controlled trials are required to investigate this further.

Stranger Things 2: Unconventional Deployment Method of High Performance Lightweight Cement Enables Success in Complex Wells

There are advantages to using high performance lightweight cement when encountering low bottomhole pressures. The most notable are maintaining wellbore stability during cement placement and the isolation of potential flow zones to achieve the wellbore construction objectives. Several complex wells sought these advantages for similar situations. A review of the deployment process for using high performance lightweight cement conventionally, including the quality assurance measures, initially deemed it as not a viable option. As the complex wells needed a technical solution, an unconventional deployment method for high performance lightweight cement enabled its use while simplifying and improving quality assurance; allowing achievement of the isolation requirements.

Overcoming Lost Circulation Risks in Low Fracture Gradient Formations with a New Tailored Spacer System

In certain regions of oil and gas operations, lost circulation is a common occurrence, especially when a majority of the openhole exposed during primary cementing is carbonate-based formations. This can lead to lost circulation risks in most applications. To overcome lost circulation risks during primary cementing, a new tailored spacer system shows to improve the cement placement success. The manuscript discusses the quality assurance and performance testing with field cases demonstrating the value contributions of the spacer for achieving zonal isolation requirements as well as the top of cement objectives. The work efforts presented shows a spacer meeting and sometimes showing incremental wellbore strengthening in comparison to the published literature for existing available spacers used to overcome similar lost circulation risks.

Quarantine and isolation facility: A State Health Department’s response to the COVID-19 pandemic

Background: State Health Departments are at the helm of addressing the myriad needs during the COVID-19 pandemic, including those of vulnerable populations who do not have a place to self-isolate or quarantine to prevent the spread. An estimated 5,000 Arkansas residents face homelessness and are at increased risk of contracting and spreading COVID-19. Additionally, those living in multigenerational families face similar challenges.Objective: We share our experiences and lessons learned in planning, executing, and maintaining a quarantine and isolation facility for vulnerable population during the COVID-19 pandemic.Setting and patients: A 29-bed quarantine and isolation facility was instituted and maintained by the Arkansas Department of Health to meet the quarantine and isolation needs of vulnerable populations. Outcomes and conclusions: As the COVID-19 pandemic persists, need for a facility to meet quarantine and isolation requirements of vulnerable population is not just a critical mitigation strategy but is an ethical imperative.

Wellbore Stabilizing Technology Enhances Cementing Efforts in the North Sea

North Sea lithologies are often complex creating a difficult environment to deliver effective zonal isolation with standard cementing practices. With ever-present weak, fractured, and unconsolidated formations, the practice of fully lifting heavier cement up the annular gap between the formation and the casing or liner often times compromises the formation and the cement integrity. Wellbore Stabilizing (WBS) technology has been shown capable of providing zonal isolation under these difficult conditions. A cementing spacer has been developed that incorporates WBS technology providing a simple way to deliver the technology in front of any cement job, without compromising the cement integrity or requiring any last-minute slurry design or redesign. By separating the placement of the WBS technology from the cement itself, the cement slurry can be designed with the sole focus being on the interval's zonal isolation requirements. On Askepott wells in the Norwegian part of the North Sea, the Nordland weak zone is encountered after drilling out the 30-inch shoe from the Oseberg Vest H template. Cement back to the seafloor is required when cementing the 20-in casing in these 26-in. holes. Prior to the introduction of the WBS technology, pressure had been observed on the D-annulus, hinting at a lack of sufficient cement circulation. With assistance from this new WBS spacer, pressure is no longer observed in the D-annulus indicating the cement is now being circulated back inside of the conductor string. The WBS spacer has also been used successfully ahead of cement across the production interval in wells where losses were typically expected, and again full returns were observed. Normally cement spacers are utilized to separate the drilling fluid from the cement as these two fluids are normally incompatible with each other and to help push the drilling fluid out of the well so the annulus may be completely filled with cement. If the drilling fluid is not successfully displaced from the annular space, the zonal isolation intended by the primary cement job is usually less than ideal. In addition to these standard functions in preparation for cementing operations, this specialized WBS spacer also can prevent loss of cement to the formation.

Fiducial qT resummation of color-singlet processes at N3LL+NNLO

We present a framework for qT resummation at N3LL+NNLO accuracy for arbitrary color-singlet processes based on a factorization theorem in SCET. Our implementation CuTe-MCFM is fully differential in the Born kinematics and matches to large-qT fixed-order predictions at relative order $$ {\alpha}_s^2 $$ α s 2 . It provides an efficient way to estimate uncertainties from fixed-order truncation, resummation, and parton distribution functions. In addition to W±, Z and H production, also the diboson processes γγ, Zγ, ZH and W±H are available, including decays. We discuss and exemplify the framework with several direct comparisons to experimental measurements as well as inclusive benchmark results. In particular, we present novel results for γγ and Zγ at N3LL+NNLO and discuss in detail the power corrections induced by photon isolation requirements.